Buggy code:
public class ModelDescriptionValidator { private static final Map < String , ModelDescriptionValidator . ArbitraryDescriptorValidator > VALID_RESOURCE_KEYS ; private static final Map < String , ModelDescriptionValidator . ArbitraryDescriptorValidator > VALID_CHILD_TYPE_KEYS ; private static final Map < String , ModelDescriptionValidator . AttributeOrParameterArbitraryDescriptorValidator > VALID_ATTRIBUTE_KEYS ; private static final Map < String , ModelDescriptionValidator . ArbitraryDescriptorValidator > VALID_OPERATION_KEYS ; private static final Map < String , ModelDescriptionValidator . AttributeOrParameterArbitraryDescriptorValidator > VALID_PARAMETER_KEYS ; private final List < ModelDescriptionValidator . ValidationFailure > errors ; private final ModelNode address ; private final ModelNode description ; private final ModelDescriptionValidator . ValidationConfiguration validationConfiguration ; public ModelDescriptionValidator ( ModelNode address , ModelNode description , ModelDescriptionValidator . ValidationConfiguration validationConfiguration ) { } private ModelDescriptionValidator ( List < ModelDescriptionValidator . ValidationFailure > errors , ModelNode address , ModelNode description , ModelDescriptionValidator . ValidationConfiguration validationConfiguration ) { } public List < ModelDescriptionValidator . ValidationFailure > validateResource ( ) { } private void validateAttributes ( ModelNode attributes ) { } private void validateOperations ( ModelNode operations ) { } private void validateChildren ( ModelNode children ) { for ( String type : children . keys ( ) ) { ModelNode typeNode = children . get ( type ) ; for ( String key : typeNode . keys ( ) ) { ModelDescriptionValidator . ArbitraryDescriptorValidator validator = ModelDescriptionValidator . VALID_CHILD_TYPE_KEYS . get ( key ) ; if ( validator == null ) { errors . add ( new ModelDescriptionValidator . ValidationFailure ( ( ( ( ( "Invalid<seq2seq4repair_space>key<seq2seq4repair_space>'" + key ) + "'<seq2seq4repair_space>found<seq2seq4repair_space>for<seq2seq4repair_space>child<seq2seq4repair_space>type<seq2seq4repair_space>'" ) + type ) + "'" ) , address ) ) ; } else { if ( typeNode . hasDefined ( key ) ) { String error = validator . validate ( typeNode , key ) ; if ( error != null ) { errors . add ( new ModelDescriptionValidator . ValidationFailure ( error , address ) ) ; } } else { if ( ! ( key . equals ( MODEL_DESCRIPTION ) ) ) { errors . add ( new ModelDescriptionValidator . ValidationFailure ( ( ( ( ( "Empty<seq2seq4repair_space>key<seq2seq4repair_space>'" + key ) + "'<seq2seq4repair_space>found<seq2seq4repair_space>for<seq2seq4repair_space>child<seq2seq4repair_space>type<seq2seq4repair_space>'" ) + type ) + "'" ) , address ) ) ; } } } } if ( ! ( typeNode . hasDefined ( DESCRIPTION ) ) ) { <START_BUG> errors . add ( new ModelDescriptionValidator . ValidationFailure ( ( ( "Missing<seq2seq4repair_space>description<seq2seq4repair_space>for<seq2seq4repair_space>child<seq2seq4repair_space>type<seq2seq4repair_space>'" + type ) + "'" ) , address ) ) ; <END_BUG> } ModelNode childType = typeNode . get ( MODEL_DESCRIPTION ) ; if ( ! ( childType . isDefined ( ) ) ) { errors . add ( new ModelDescriptionValidator . ValidationFailure ( ( ( "No<seq2seq4repair_space>model<seq2seq4repair_space>description<seq2seq4repair_space>for<seq2seq4repair_space>child<seq2seq4repair_space>'" + type ) + "'" ) , address ) ) ; continue ; } for ( String child : childType . keys ( ) ) { ModelNode childAddress = address . clone ( ) ; childAddress . add ( type , child ) ; ModelDescriptionValidator childValidator = new ModelDescriptionValidator ( errors , childAddress , childType . get ( child ) , validationConfiguration ) ; childValidator . validateResource ( ) ; } } } private void validateAttributeOrParameter ( ModelDescriptionValidator . AttributeValidationElement validationElement , ModelNode rawDescription ) { } private void validateAttributeOrParameter ( ModelDescriptionValidator . AttributeValidationElement validationElement , ModelNode rawDescription , ModelNode currentDescription ) { } public interface AttributeOrParameterArbitraryDescriptorValidator { String validate ( ModelType currentType , ModelNode currentNode , String descriptor ) { } } public interface ArbitraryDescriptorValidator { String validate ( ModelNode currentNode , String descriptor ) { } } private static class SimpleIntDescriptorValidator implements ModelDescriptionValidator . ArbitraryDescriptorValidator { static final ModelDescriptionValidator . SimpleIntDescriptorValidator INSTANCE = new ModelDescriptionValidator . SimpleIntDescriptorValidator ( ) ; @ Override public String validate ( ModelNode currentNode , String descriptor ) { } } private static class NumericDescriptorValidator implements ModelDescriptionValidator . AttributeOrParameterArbitraryDescriptorValidator { static final ModelDescriptionValidator . NumericDescriptorValidator INSTANCE = new ModelDescriptionValidator . NumericDescriptorValidator ( ) ; public String validate ( ModelType currentType , ModelNode currentNode , String descriptor ) { } } private static class LengthDescriptorValidator implements ModelDescriptionValidator . AttributeOrParameterArbitraryDescriptorValidator { static final ModelDescriptionValidator . LengthDescriptorValidator INSTANCE = new ModelDescriptionValidator . LengthDescriptorValidator ( ) ; public String validate ( ModelType currentType , ModelNode currentNode , String descriptor ) { } } private static class BooleanDescriptorValidator implements ModelDescriptionValidator . ArbitraryDescriptorValidator , ModelDescriptionValidator . AttributeOrParameterArbitraryDescriptorValidator { static final ModelDescriptionValidator . BooleanDescriptorValidator INSTANCE = new ModelDescriptionValidator . BooleanDescriptorValidator ( ) ; public String validate ( ModelType currentType , ModelNode currentNode , String descriptor ) { } @ Override public String validate ( ModelNode currentNode , String descriptor ) { } } private static class AccessTypeDescriptorValidator implements ModelDescriptionValidator . AttributeOrParameterArbitraryDescriptorValidator { static final ModelDescriptionValidator . AccessTypeDescriptorValidator INSTANCE = new ModelDescriptionValidator . AccessTypeDescriptorValidator ( ) ; public String validate ( ModelType currentType , ModelNode currentNode , String descriptor ) { } } private static class StorageDescriptorValidator implements ModelDescriptionValidator . AttributeOrParameterArbitraryDescriptorValidator { static final ModelDescriptionValidator . StorageDescriptorValidator INSTANCE = new ModelDescriptionValidator . StorageDescriptorValidator ( ) ; public String validate ( ModelType currentType , ModelNode currentNode , String descriptor ) { } } private static class NullDescriptorValidator implements ModelDescriptionValidator . ArbitraryDescriptorValidator , ModelDescriptionValidator . AttributeOrParameterArbitraryDescriptorValidator { static final ModelDescriptionValidator . NullDescriptorValidator INSTANCE = new ModelDescriptionValidator . NullDescriptorValidator ( ) ; @ Override public String validate ( ModelType currentType , ModelNode currentNode , String descriptor ) { } @ Override public String validate ( ModelNode currentNode , String descriptor ) { } } private static class StringListValidator implements ModelDescriptionValidator . ArbitraryDescriptorValidator , ModelDescriptionValidator . AttributeOrParameterArbitraryDescriptorValidator { static final ModelDescriptionValidator . StringListValidator INSTANCE = new ModelDescriptionValidator . StringListValidator ( ) ; @ Override public String validate ( ModelType currentType , ModelNode currentNode , String descriptor ) { } @ Override public String validate ( ModelNode currentNode , String descriptor ) { } } public static class ValidationConfiguration { private Map < ModelNode , Set < String > > nullValueTypeAttributes = new HashMap < ModelNode , Set < String > > ( ) ;

Fix:
errors . add ( new ModelDescriptionValidator . ValidationFailure ( ( ( ( ( "Missing<seq2seq4repair_space>description<seq2seq4repair_space>for<seq2seq4repair_space>child<seq2seq4repair_space>type<seq2seq4repair_space>'" + type ) + "'<seq2seq4repair_space>on<seq2seq4repair_space>ModelNode<seq2seq4repair_space>'" ) + ( typeNode . toString ( ) ) ) + "'" ) , address ) ) ;